CHARACTERIZATION OF PREGNANCY ASSOCIATED GLYCOPROTEIN-1GENE IN WHITE FULANI, MUTURU AND N'DAMA CATTLE BREEDS IN NIGERIA

Pregnancy associated glycoptotein-1 (PAG-1) gene belong to a large family of aspartic peptidases expressed exclusively by different placental cells of mammalian species. This study was conducted to characterize exon 4 (the most polymorphic exon) of PAG-l gene in White Fulani, Muturu and N'Dama breeds of cattle. Blood samples from seventy-four (74) animals (25 Muturu, 25 White Fulani and 24 from N'Dama) were collected from two farms in Southwest, Nigeria. Exon 4 and the surrounding intron 5 of bovine PAG-l gene were amplified and sequenced. Single nucleotide polymorphisms (SNPs) in the gene were detected using codon code aligner. Estimates of population genetic statistics and diversity were obtained using Arlequin 2.0 and DnaSP respectively. The protein motifs and its secondary structure were predicted. Four SNPs: 173G>A (χ2 =1.75), 244C>A (χ2=11.11), 377C>A, (χ2=0.89) and 392G>A (χ2=0.51) were observed in exon 4 of White Fulani, while two, 620A>G (χ2=0.01) and 630G>A (χ2=17.38), were observed in intron 5 of Muturu. Mutation 244C>A (χ2=10.41) was shared by White Fulani and N'Dama. Eight haplotypes were identified in exon 4 and the surrounding intron 5 of bovine PAG-l gene with White Fulani having the high...est haplotype diversity (0.82), nucleotide diversity (2.7 x 10-3) and average number of nucleotide differences (1.74). The AMOVA results revealed that the percent...age of variation within the population for gene in the three breeds was greater than variation among the pop...ulations. The result indicated no genetic differentiation between Muturu and N'Dama. Three motifs (Protein kinase C-phosphorylation, N-myristoylation and Casein Kinase II phosphorylation sites) were shared by the three cattle breeds. Protein structure prediction analysis classified exon 4 of bovine PAG-l as mixed folding consisting of 25.97% alpha helix among the three cattle breeds. The SNPs observed in these cattle breeds could be used for association studies with pregnancy related traits.